i just replaced mine - the seal is about £8 from VW - DO NOT get the one from online parts stores - the size is the same but the original has an additional seal lip on the inside.
You need to remove the gearbox mount - bottle jack and a piece of wood to support the gearbox, jack it just enough to off load the mount.
5 bolts - 2 in the subframe and 3 in the mount bracket, 2 are clear visible the 3rd is behind the mount and accessed through the mount. Turn the wheel so it pointing outwards and then you look through the mount and you will see it.
you need a 16mm socket plus a medium and long extension.
Use a screwdriver and punch a hole through the seal
but just enough to get into the seal otherwise you will hit components on the inside!!!!
Lever the seal out, lubricate the new seal lip , fit it in position and then with a piece of wood you can work the seal into position and tap it in.
If you remove the wheel arch retaining screw above the gearbox mount you can pull the liner away to give you a bit more access.
It look me an hour start to finish on my driveway with the wheel on.
Charging 5 hours is taking the piss !!!
As you have had a substantial oil loss you will need to refill the gearbox.
The seal fails as its a metal cap and the metal is exposed in the grooves in the cap hence the rust on the cap. The new version doesn't have any exposed metal, i took no chances and overcoated it.
